Deadlocking mechanism blocker



Aug. 22, 1967 F. J. RUSSELL ETAL 3,337,259 DE/\DLOCKING FY .JCHXNISM BLOCKER 2 Sheets-Sheet 1 Filed May 5, 1964 L L 5mm a mum m NE N M 5 J 1 56 W 20 F2 Ym 05/ Fv J. RUSSELL ETAL DEADLOCKIN} MECHANISM BLOCKER Aug. 22, 1967 2 Sheets-Sheet 2 Filed May 5, 1964 F1250 J, RUSSELL R0652 J. NOL/N INVENTORS ATTOIZN Y United States Patent 3,337,250 DEADLOCKING MECHANISM BLOCKER Fred J. Russell, 8635 Otis St., South Gate, Calif. 90280, and Roger J. Nolin, Monterey Park, Calif.; said Nolin assignor to said Russell Filed May 5, 1964, Ser. No. 365,016 3 Claims. (Cl. 292--210) The invention here under consideration is embodied in a door lock with special reference to door locks frequently identified as unit locks, the invention being more particularly concerned with a guard bolt for the main latch bolt.

For extra security in locks of this nature, a guard bolt is provided in addition to the conventional latch bolt, the action of which is to make the lock more tamperproof. Guard bolts take various forms, some lying immediately adjacent the latch bolt and others spaced from the latch bolt to allow more room for the working mechanism. The purpose of such guard bolts, however, is essentially the same, namely, to act in such fashion that, when depressed, a physical block is interposed in the latch bolt action so that the latch bolt cannot be pried into a door opening position by unauthorized means. The customary fashion for manipulating a guard bolt of this kind is to have it so mounted on the frame that when the door is closed, the guard bolt is depressed by the strike plate, causing the desired action to take place, the guard bolt remaining in depressed position as long as the door remains closed, and thereafter springing to extended position, whereupon the blocking mechanism is automatically released.

One of the common objections to many types of guard bolt action is sluggishness in that the guard bolt may not operate at the right moment and consequently fail to reach a secure guarding position. In some mechanisms, this means that the guard bolt action cannot take place and, in others, that damage and undue wear may result to the mechanism. Other types of mechanisms for this purpose are somewhat complicated in the number of intricate parts, which often make the device less dependable and relatively expensive.

It is, therefore, among the objects of the invention to provide a new and improved guard bolt action which is fast acting and which may take place actually before the guard bolt is fully depressed.

Another object of the invention is to provide a new and improved guard bolt action which contains relatively few parts, the parts, however, being positive acting and rugged in structure and operation.

Still another object of the invention is to provide a new and improved guard bolt action which makes use of a well balanced leverage swinging about a pivot point, so that ample movement to perform the guard bolt action is derived from relatively little movement of the guard bolt itself.

Still another object of the invention is to provide a compact, positive acting guard bolt mechanism which takes up relatively little space in the frame of the device and therefore permits the various mechanisms to be separately mounted and contributes materially to a lock structure which is easy to build and maintain in good working order.

With these and other objects in view, the invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained, as hereinafter set forth, pointed 3,337,250 Patented Aug. 22, 1967 FIGURE 2 is a longitudinal sectional View of the working parts of the device with the latch bolt and guard bolt in extended positions.

FIGURE 3 is a view similar to FIGURE 2 but showing parts of the device with the latch bolt and guard bolt in extended positions.

FIGURE 3 is a view similar to FIGURE 2 but showing the door in closed position, with the latch bolt received in a strike plate recess and with the guard bolt in the retracted position it woud have when in engagement with the strike plate, the latch bolt being shown in solid lines, moved to a position where the guard bolt action becomes operative.

FIGURE 4 is a plan view on the line 4-4 of FIG- URE 2, with a wall of the frame broken away to reveal the working parts.

FIGURE 5 is a plan view similar to FIGURE 4 but showing the door jamb strike plate in section and the guard bolt depressed in the relationship shown in FIG- URE 3. I

FIGURE 6 is a fragmentary sectional view on the line 66 of FIGURE 3.

FIGURE 7 is a perspective view of the main element of the blocker structure shown separately as an aid to an understanding of its structure and operation.

In an embodiment of the device which has been chosen for the purpose of illustration, the mechanism is pictured and described in connection with a unit type lock, though it should be recognized that the mechanism broadly need not necessarily be confined to locks of this particular description and construction.

A unit type lock indicated generally by the reference character 10 is shown installed in a door 11, the lock 10 being provided with a knob 12, a rose 13 overlying a side face 14 of the door and part of a frame 15 shown within a cutout 16 in an edge 17 of the door 11.

In the chosen embodiment, the frame 15 may be construed as consisting of a front wall 18, side walls 19 and 20, end walls like the end wall 21 visible in FIGURES 2 and 3, and a rear wall 22. In the front wall 18 is a relatively large opening 23 in which is located a latch bolt 24 and a relatively small opening 25 in which is located a guard bolt 26.

For purposes of illustration, the latch bolt 24 is shown as a tiltably mounted latch bolt 24 secured to the frame 15 by employment of a pivot pin 27. The pivot pin 27 may be made long enough so that it serves also as a means of tiltably mounting the guard bolt 26 on the frame 15. Extending inwardly from the latch bolt 24 is a tailpiece 28 which is pivotally secured to the latch bolt 24 by means of a pin 29. The tailpiece 28 extends through a hole 30 in the rear wall 22. A cross bar 33 at the innermost end of the tailpiece 28 is adapted to engage a retractor (not shown) so that, in a conventional fashion,

' movement of the retractor will be transferred to the tailpiece 28 through the cross bar 33, and the latch bolt 24 can by this action be withdrawn from the extended position of FIGURES 2, 3, and 4 to a retracted position, not specifically illustrated. If desired, a spring 34 may be provided acting between the rear wall 22 and the inner side of the latch bolt 24, serving thereby as a return spring for the latch bolt 24.

As previously indicated, it is the function of the guard bolt 26 to block retraction of the latch bolt 24. Mechanism for accomplishing this is embodied in part in a blocker indicated generally by the reference character 40 which may be described as a bracket having bracket arms 41, 41 at its inner end and a pivot pin 42 pivotally mounting the blocker 40 upon the side walls 19 and 20 of the frame 15. A platform 43 forming part of the blocker 40 extends transversely with respect to the movement generally of the guard bolt 26, as shown in FIGURE 4. The

platform 43 is also tilted slightly, as shown in FIGURE 2. An extension 44 of the blocker 40 carries at its free end a projection 45. It is the projection 45 which does the blocking for which the blocker 40 is designed. The latch bolt 24 may be described as having what may be designated a shelf 46 on its inner side, which serves as a specific area against which the projection 45 is projected.

In order to manipulate the blocker 40, a trip arm 47 is made use of. At its outer end, the trip arm 47 is pivotally attached to the guard bolt 26 by employment of a pivot pin 48, and the pivot pin 48 may at the same time be made use of as a stop to limit outward movement of the guard bolt 26 about the pivot pin 27 on which it is mounted. In the platform 43 is an aperture 49, and the trip arm 47 projects through the aperture 49, where it is bent to form a finger 50. It is important to note that the trip arm 47 has a smooth, sliding fit in the aperture 49 and that the finger 50 has a point of contact 51 (see FIG- URE 2) with the inner or under side of the platform 43 which, for purposes of explanation, should be noted as having a predetermined distance offset with respect to the center of rotation of the pivot pin 42.

A spring 52, serving as a compression spring, surrounds the trip arm 47 and presses at its outer end against a surface 53 on the inside of the guard bolt 26. At its other end, the spring 52 is pressed into engagement with the platform 43. In this connection, it should be noted that the point of engagement of the spring 52 with the platform 43 occurs at a distance from the pivot pin 42 less than the distance between the point of contact 51 of the finger 50 and the pivot pin 42. In this respect, it may be said that the brackets 41 and 41' and the platform 43 thereon serves as a third class lever, with an application of force at the point of contact 51 at a distance from the fulcrum, which is the center of rotation of the pivot pin 42, greater than the distance from the fulcrum to the location of resistance supplied by the spring 52.

The mechanism described is the guard bolt mechanism which serves to block retraction of the latch bolt 24 when the door 11 is closed, as shown in FIGURES 3 and 5. Blocking is accomplished by moving the guard bolt 26 to a retracted position. This happens when the door 11 closes and when the guard bolt 26 engages a flat portion of a strike plate 55 which is mounted on a door jamb 56. The strike plate 55, incidentally, may be provided with a recess 57 located in a hole 58 made at an appropriate location on the door jamb 56. As the guard bolt 26 is depressed, or in other words, pivotally swung about the pivot pin 27, the trip arm 47 moves inwardly or in a direction from left to right, as viewed in FIGURES 2, 3, 4, and 5. When this occurs, the finger 50 and its point of contact 51 is pushed entirely clear of the platform 43, as advantageously shown in FIGURE 3. As a consequence, the only force then applied against the blocker 40 is the force exerted by the spring 52 pressing upon the platform 43 at a location offset with respect to the pivot pin 42, and this force tends to rotate the blocker 40 in a counter-clockwise direction, as viewed in FIGURES 2 and 3, moving the projection 45 from the position of FIGURE 2 to the position of FIGURE 3. In the position of FIG- URE 3, the projection 45 is opposite the shelf 46 of the latch bolt 24, and consequently the latch bolt 24 cannot be retracted and the door 11 cannot be opened by unauthorized means as by prying back the latch bolt 24 with some lock picking instrument.

Accessory means for decommissioning the guard bolt thereby to enable withdrawal of the latch bolt in an authorized manner are disclosed and described in detail in copending application Ser. No. 353,740, filed Mar. 23, 1964; Ser. No. 353,741, filed Mar. 23, 1964; Ser. No.

S 353,742, filed Mar. 23, 1964; and Ser. No. 373,429, filed June 8, 1964.

While the invention has herein been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices.

Having described the invention, what is claimed as new in support of Letters Patent is:

1. In a door lock, which includes a frame and a latch bolt having a reciprocatably movable mounting on said frame for movement between extended and retracted positions; a guard bolt assembly including a guard bolt having a movable mounting on said frame for movement between extended and retracted positions, a blocker for said latch bolt having at one end a pivotal connection to said frame, said blocker having a scope of movement be tween a blocking position for said latch bolt and a clear position free of said latch bolt, a platform on said blocker in axial alignment with the guard bolt, a projection on said blocker comprising a part of the blocker adapted to be positioned behind said latch bolt, and means connected to said guard bolt for moving said blocker between said blocking and clear positions, said means comrising a trip arm having at one end a movable connection to said guard bolt, a finger on the other end of said trip arm having a point of engagement with said platform on a side thereof remote from the guard bolt and at a first distance spaced radially from said pivotal connection and acting in one rotational direction about said pivotal connection, a coiled spring having one end thereof in engagement with said guard bolt and having the other end thereof in engagement with the side of the platform facing said guard bolt at a second distance spaced radially from said pivotal connection, said second distance being less than said first distance whereby, upon movement of said guard bolt to retracted position, said projection is shifted to said blocking position in response to action of said spring between said guard bolt and said platform and, upon movement of said guard bolt to extended position, said projection is shifted to clear position in response to action of said spring between said guard bolt, said trip arm and the finger thereon, and said platform.

2. A guard bolt assembly according to claim 1, wherein said platform has an aperture extending therethrough in alignment with said trip arm, and said trip arm has a position extending through said aperture from one side to the other of said platform, the finger on said trip arm having a location extending away from the aperture to a point of engagement with said platform at a location further from said pivotal connection than the location of said aperture.

3. A guard bolt assembly according to claim 2, wherein said coiled spring has a position encircling said trip arm and wherein the end of the spring adjacent said platform extends around said aperture.

References Cited UNITED STATES PATENTS 834,994 11/ 1906 Phelps -151 938,921 11/1909 Voight 70151 2,403,597 7/ 1946 Hill'gren 70-151 X 2,591,647 4/ 1952 Welch 7015l 2,730,391 1/1956 Rayburn 70--151 X 2,742,310 4/1956 Russell 70151 X 2,768,014 10/1956 Golden et a1 292169 2,821,849 2/ 1958 Schweitzer 292222 3,144,266 8/1964 Schmid et al 292169 MARVIN A. CHAMPION, Primary Examiner.

EDWARD C. ALLEN, RICHARD E. MOORE,

Examiners. J. R. MOSES, Assistant Examiner. 

1. IN A DOOR LOCK, WHICH INCLUDES A FRAME AND A LATCH BOLT HAVING A RECIPROCATABLY MOVABLE MOUNTING ON SAID FRAME FOR MOVEMENT BETWEEN EXTENDED AND RETRACTED POSITIONS: A GUARD BOLT ASSEMBLY INCLUDING A GUARD BOLT HAVING A MOVABLE MOUNTING ON SAID FRAME FOR MOVEMENT BETWEEN EXTENDED AND RETRACTED POSITIONS, A BLOCKER FOR SAID LATCH BOLT HAVING AT ONE END A PIVOTAL CONNECTION TO SAID FRAME, SAID BLOCKER HAVING A SCOPE OF MOVEMENT BETWEEN A BLOCKING POSITION FOR SAID LATCH BOLT AND A CLEAR POSITION FREE OF SAID LATCH BOLT, A PLATFORM ON SAID BLOCKER IN AXIAL ALIGNMENT WITH THE GUARD BOLT, A PROJECTION ON SAID BLOCKER COMPRISING A PART OF THE BLOCKER ADAPTED TO BE POSITIONED BEHIND SAID LATCH BOLT, AND MEANS CONNECTED TO SAID GUARD BOLT FOR MOVING SAID BLOCKER BETWEEN SAID BLOCKING AND CLEAR POSITIONS, SAID MEANS COMPRISING A TRIP ARM HAVING AT ONE END A MOVABLE CONNECTION TO SAID GUARD BOLT, A FINGER ON THE OTHER END OF SAID TRIP ARM HAVING A POINT OF ENGAGEMENT WITH SAID PLATFORM ON A SIDE THEREOF REMOTE FROM THE GUARD BOLT AND AT A FIRST DISTANCE SPACED RADIALLY FROM SAID PIVOTAL CONNECTION AND ACTING IN ONE ROTATIONAL DIRECTION ABOUT SAID PIVOTAL CONNECTION, A COILED SPRING HAVING ONE END THEREOF IN ENGAGEMENT WITH SAID GUARD BOLT AND HAVING THE OTHER END THEREOF IN ENGAGEMENT WITH THE SIDE OF THE PLATFORM FACING SAID GUARD BOLT AT A SECOND DISTANCE SPACED RADIALLY FROM SAID PIVOTAL CONNECTION, SAID SECOND DISTANCE BEING LESS THAN SAID FIRST DISTANCE WHEREBY, UPON MOVEMENT OF SAID GUARD BOLT TO RETRACTED POSITION, SAID PROJECTION IS SHIFTED TO SAID BLOCKING POSITION IN RESPONSE TO ACTION OF SAID SPRING BETWEEN SAID GUARD BOLT AND SAID PLATFORM AND, UPON MOVEMENT OF SAID GUARD BOLT TO EXTENDED POSITION, SAID PROJECTION IS SHIFTED TO CLEAR POSITION IN RESPONSE TO ACTION OF SAID SPRING BETWEEN SAID GUARD BOLT, SAID TIP ARM AND THE FINGER THEREON, AND SAID PLATFORM. 